Washington — House lawmakers emerging from a classified, closed-door briefing with an internal government watchdog on Friday said they remained frustrated in their attempts to get more information about explosive whistleblower claims made about unidentified anomalous phenomena, or UAPs.

Thomas Monheim, the inspector general of the intelligence community, briefed members of the House Oversight Committee's national security subcommittee on Capitol Hill. The meeting came months after the subcommittee held a high-profile public hearing that featured tantalizing testimony from a former military intelligence officer-turned-whistleblower named David Grusch.

At the hearing in July, Grusch said he was informed of "a multi-decade UAP crash retrieval and reverse-engineering program" and accused the military of misappropriating funds to shield these operations from congressional oversight. He claimed he had interviewed officials who had direct knowledge of aircraft with "nonhuman" origins, and that so-called "biologics" were recovered from some craft. The Pentagon denied his claims.

The subcommittee has been leading the charge to improve transparency about what the government knows about anomalous phenomena. Rep. Glenn Grothman, a Republican from Wisconsin and the subcommittee's chairman, said before Friday's meeting that lawmakers were looking "to track down exactly what the military thinks of individual instances of these objects flying around."

The UAP briefing

Several lawmakers who emerged from the briefing on Capitol Hill said they were frustrated by the lack of new information about Grusch's allegations. Rep. Raja Krishnamoorthi, a Democrat from Illinois, told reporters that lawmakers "haven't gotten the answers that we need."

"Everybody is wondering about the substance of those claims. And until we actually look at those specifically, and try to get answers about those, those claims are just going to be out there," he said. "And so that's what we needed to kind of delve into. And unfortunately, I just wasted time in there not kind of figuring out whether those were true."

GOP Rep. Tim Burchett of Tennessee said the subcommittee was playing "Whack-a-Mole" in its efforts to elicit information from the executive branch: "You go to the next [briefing], until we get some answers."

Others struck a more positive tone. Rep. Robert Garcia, the top Democrat on the subcommittee, said he "would have loved to receive much more information," but added that "it's reasonable to say that everyone that was in the room received probably new information."

Garcia and Grothmann unveiled a new bipartisan bill this week that would enable civilian pilots and personnel to report UAP encounters with the FAA, which would then be required to send those reports to the Pentagon office investigating the phenomena. The bill, known as the Safe Airspace for Americans Act, would also offer protections for those who come forward.

Democratic Rep. Jared Moskowitz of Florida said the meeting was "the first real briefing that we've had, that we've now made, I would say, progress on some of the claims Mr. Grusch has made."

"This is the first time we kind of got a ruling on what the IG thinks of those claims. And so this meeting, unlike the one we had previously when we did this briefing, this one actually moved the needle," Moskowitz said.

What are UAPs?

"Unidentified anomalous phenomena" is the government's formal term for what used to be called unidentified flying objects, or UFOs. They encompass a broad range of strange objects or data points detected in the air, on land or at sea. 

The most well-known UAPs have been reported by military pilots, who typically describe round or cylindrical objects traveling at impossibly high speeds with no apparent means of propulsion. Some of the objects have been caught on video.

The military has made a point of improving avenues for pilots to report UAPs in recent years and worked to reduce the stigma once associated with doing so. The Pentagon office dedicated to examining the encounters has received hundreds of reports in recent years. 

Many UAP reports have been shown to have innocuous origins, but a subset has defied easy explanation. The issue has gained renewed attention from lawmakers over the past few years, with heightened concerns about the national security implications of unidentified objects flying in U.S. airspace.

Stefan Becket

Stefan Becket is assistant managing editor, digital politics, for CBSNews.com. He helps oversee a team covering the White House, Congress, the Supreme Court, immigration and federal law enforcement.

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